This proposal seeks funds for the purchase of an isothermal titration calorimeter (ITC), capable of measuring complete thermodynamic profiles for interacting systems as a function of temperature and solution conditions in single experiments. The ultrasensitive iTC200 microcalorimeter from MicroCal, Inc. (Amherst, MA) was selected because of its higher sensitivity (4-6 times) over other commercially available calorimeters;it also requires smaller amounts (one tenth) of the precious protein and other types of sample materials. It is also capable of measuring subminute ligand binding and enzyme kinetics with a millidegree peltier temperature control in the 2 degrees C to 80 degrees C temperature range. This ITC instrument will enhance a central facility for the measurement of biomolecular interactions in the Department of Pharmaceutical Sciences at the University of Nebraska Medical Center (UNMC). This facility will benefit the research of eleven user groups from the Department of Pharmaceutical Sciences (College of Pharmacy), Department of Biochemistry and Molecular Biology (College of Medicine) and Eppley Institute for Research in Cancer at UNMC. Each group includes several graduate students and postdoctoral fellows who will make heavy use of this instrumentation in their research projects. Detailed descriptions of the primary research projects which are proposed by each user group are included, as are arrangements for the management, maintenance, and organization of user groups. Their research projects are geared to measure complete thermodynamic binding profiles for the formation of macromolecular complexes. This includes protein-protein, DNA-protein, protein-polymer, polymer-lipid membranes, DNA-DNA and DNA-RNA, DNA-polymer and small ligand-polymer complexes. The acquisition of this calorimeter will help with stronger and new collaborations among colleagues and their laboratory groups, enhancing the training of young scientists at UNMC with calorimetric techniques. Furthermore, it will help in the creation of a Center for Pharmaceutical Biophysics at UNMC, which is a current strategic initiative of the Department of Pharmaceutical Sciences.